System and method for preventing fouling and/or corrosion on vessels and marine objects

ABSTRACT

A corrosion or fouling prevention system for preventing the fouling or corrosion of a vessel or an aquatic object having a surface in contact with seawater and/or brackish water in an aquatic environment, the system comprising: a flexible and non-permeable barrier that extends about a surface of the vessel or aquatic object to avoid direct contact between the surface and the seawater and/or brackish water, an attachment structure for attachment of the barrier relative to the vessel or aquatic object to position the barrier in a spaced apart arrangement from the surface of the vessel to define an internal volume in between the surface of the vessel of the object and the barrier to receive a fluid that has a composition that is different to the aquatic environment.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of International patent application No. PCT/AU2018/051307, filed on Dec. 6, 2018 and titled SYSTEM AND METHOD FOR PREVENTING FOULING AND/OR CORROSION ON VESSELS AND MARINE OBJECTS (“the '307 PCT Application”). The '307 PCT Application includes a claim for the benefit of priority to the Dec. 6, 2017 filing date of Australian Provisional Patent Application No. 2017904918, titled SYSTEM AND METHOD FOR PREVENTING FOULING AND/OR CORROSION ON VESSELS AND MARINE OBJECTS (“the '918 Australian Provisional Application”). The entire disclosures of the '307 PCT Application and the '918 Australian Provisional Application are hereby incorporated herein.

TECHNICAL FIELD

The present invention relates to the prevention of fouling and/or corrosion on objects in an aquatic environment.

BACKGROUND

Any references to methods, apparatus or documents of the prior art are not to be taken as constituting any evidence or admission that they formed, or form part of the common general knowledge.

Barnacles, algae, and marine organisms often build up on underwater structures, such as hulls of boats, which process is generally referred to as biological fouling. In the case of boats, the presence of fouling may increase resistance (drag) in the water, which in turn increases fuel consumption. Fouling can, however, also cause damage to the hull or propulsion system. Similar problems exist with other underwater structures, such as subsea machinery.

Anti-fouling coatings are often applied to these underwater structures to prevent, or at least reduce the prevalence of fouling. In many cases paints including biocides are applied to the hull of boats and ships to prevent such fouling. A problem with such anti-fouling coatings is that they are often toxic to the marine environments in which they are used. In particular, the anti-fouling coatings generally wear off, and thus become distributed in waterways where they may cause damage to other types of marine life. A further problem with such anti-fouling coatings is that they are generally difficult to apply, as the boat (or other structure) must come out of water for such application. While it is possible to apply such coatings at time of manufacture, the coatings must generally be re-applied periodically.

Another problem with underwater structures is corrosion. Often paint, or similar anti-corrosion coatings, are provided on underwater structures to prevent corrosion. Similar problems, however, exist in relation to anti-corrosion coatings as are discussed above in relation to anti-fouling coatings.

As such, there is clearly a need for an improved system for preventing fouling and/or corrosion on objects in an aquatic environment.

SUMMARY

In an aspect, the invention provides a corrosion or fouling prevention system for preventing the fouling or corrosion of a vessel or an aquatic object having a surface in contact with seawater and/or brackish water in an aquatic environment, the system comprising:

a flexible and non-permeable barrier that extends about a surface of the vessel or aquatic object to avoid direct contact between the surface and the seawater and/or brackish water,

an attachment structure for attachment of the barrier relative to the vessel or aquatic object to position the barrier in a spaced apart arrangement from the surface of the vessel to define an internal volume in between the surface of the vessel of the object and the barrier to receive a fluid that has a composition that is different to the aquatic environment.

In an embodiment, the attachment structure comprises one or more floatation devices adapted for being positioned relative to the vessel or object and wherein during use the barrier is suspended in a generally downward direction relative to the floatation device to position the barrier in said spaced apart arrangement.

In an embodiment, buoyancy of the one or more floatation devices may be variable to allow the lowering or raising of the attachment structure.

In an embodiment, the floatation devices are adapted to be attached to the vessel or object.

In an embodiment, the floatation device comprises walls enclosing a hollow cavity with an inlet for receiving a fluid therein such that supplying fluid into the cavity of the floatation device results in lowering or submerging the attachment structure into the seawater and/or brackish water in a lowered position to allow said vessel or aquatic object to be positioned above the attachment structure; and a fluid removal arrangement to gradually remove fluid from the one or more cavities of the floatation device to raise the attachment structure to the surface of the seawater or brackish water to facilitate attachment of the barrier relative to the vessel or aquatic object.

In an embodiment, the corrosion or fouling prevention system further comprises a flow controller for controlling the flow of fluid into or out of the one or more cavities of the floatation devices thereby effecting movement of the attachment structure.

In an embodiment, the corrosion or fouling prevention system further comprises:

a pumping arrangement adapted to pump out sea water or brackish water from the internal volume in between the surface of the vessel of the object; and

a fluid supply arrangement to supply the fluid that has a composition that is different to the aquatic environment into the internal volume in between the surface of the vessel of the object.

In an embodiment, the corrosion or fouling prevention system further comprises one or more coupling assemblies positioned relative to the barrier and/or the attachment structure, said coupling assemblies being adapted to be coupled to the pumping arrangement and/or the fluid supply arrangement.

In an embodiment, the flotation devices further comprise one or more vents positioned to vent the cavities and release accumulation of air when the floatation devices contain pressurised fluid in the one or more cavities.

In an embodiment, the corrosion or fouling prevention system for preventing the fouling or corrosion of a vessel having a surface in contact with seawater and/or brackish water in an aquatic environment further comprises a marina attachment assembly adapted to be coupled with the attachment structure and/or the barrier to facilitate installation or removal of the corrosion or fouling prevention system relative to the vessel.

In an embodiment, the marina attachment assembly further comprises an extension member extending outwardly from the marina for attachment to the attachment structure at one or more attachment locations wherein the extension member is adapted for movement in an upward or downward to facilitate upward or downward movement of the attachment structure relative to the vessel thereby facilitating installation or removal of the corrosion or fouling prevention system relative to the vessel.

In an embodiment, the marina attachment assembly comprising one or more connectors adapted to be fluidly coupled to the fluid supply arrangement and the pumping arrangement.

In an embodiment, the fluid received in the internal volume in between the surface of the vessel of the object and the barrier is fresh water.

In an embodiment, the corrosion or fouling prevention system further comprises a sealing arrangement for sealing a portion of the barrier relative to the vessel or the marine object to prevent the sea water or brackish water from being received into the internal volume in between the surface of the vessel of the object and the barrier.

In another aspect, the invention provides a method for corrosion or fouling prevention in a vessel or an aquatic object having a surface in contact with seawater and/or brackish water in an aquatic environment, the method comprising:

-   -   a. positioning a flexible and non-permeable barrier that extends         about a surface of the vessel or aquatic object to avoid direct         contact between the surface and the seawater and/or brackish         water;     -   b. attaching an attachment structure relative to the vessel or         aquatic object to position the barrier in a spaced apart         arrangement from the surface of the vessel to define an internal         volume in between the surface of the vessel of the object and         the barrier; and     -   c. supplying a fluid into the internal volume wherein the fluid         has a composition that is different to the aquatic environment.

In an embodiment, the attachment structure comprises one or more floatation devices adapted for attachment to the vessel or object and wherein the attachment step of the method comprises suspending the barrier in a generally downward direction relative to the floatation device to position the barrier in said spaced apart arrangement.

In an embodiment, the method for corrosion or fouling prevention further comprises the steps of:

-   -   d. supplying fluid into a hollow cavity defined by walls of the         floatation devices to lower or submerge the attachment structure         into the seawater and/or brackish water into a lowered position         to allow said vessel or aquatic object to be positioned above         the attachment structure; and     -   e. remove or pump fluid out of the hollow cavity of the         floatation devices to gradually raise the floatation devices of         the attachment structure to the surface of the seawater or         brackish water for facilitating positioning of the barrier         relative to the vessel or aquatic object.

In an embodiment, the method for corrosion or fouling prevention further comprises an intermediate step of: pumping or removing any sea water or brackish water from the internal volume before the step of supplying the fluid into the internal volume in between the surface of the vessel of the object and the barrier.

In an embodiment, the method further comprises the step of coupling the attachment structure and/or the barrier to a marina attachment assembly to facilitate installation or removal of the corrosion or fouling prevention system relative to the vessel.

In an embodiment, the marina attachment assembly further comprises an extension member extending outwardly from the marina and the method comprising the additional steps of:

-   -   attaching the marina attachment assembly to the attachment         structure at one or more attachment locations;     -   lowering the extension member in a downward direction to         facilitate downward movement of the attachment structure for         positioning the attachment structure in said lowered position         before positioning the vessel or aquatic object above the         attachment structure;     -   raising the extension member in an upward direction to         facilitate upward movement of the attachment structure in the         sea water or brackish water and positioning the attachment         structure adjacent the vessel or the object at or along the         surface of the sea water or brackish water.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred features, embodiments and variations of the invention may be discerned from the following Detailed Description which provides sufficient information for those skilled in the art to perform the invention. The Detailed Description is not to be regarded as limiting the scope of the preceding Summary of the Invention in any way. The Detailed Description will make reference to a number of drawings as follows:

FIG. 1 is a section view of a marine vessel 205 being protected by a corrosion and fouling prevention system 200.

FIG. 1A is an enlarged view of a section 200A (shown in FIG. 1).

FIG. 2 is a side view of the vessel 205 with the corrosion and fouling prevention system 200 installed thereon shown in an in-use configuration.

FIG. 3 is a sectional view of the marine vessel 205 with the corrosion protection system 200 shown in a lowered configuration.

FIG. 4 is a schematic fluid supply and pumping arrangement for either (a) supplying fluid into the floatation device(s) 225 or removing fluid from the floatation devices 225.

FIG. 5 is a sectional view of the marine vessel 205 with the corrosion protection system 200 shown in a gradually raised configuration.

FIG. 6 is a sectional view of the marine vessel 205 with the corrosion protection system 200 shown in a fully raised configuration.

FIG. 7 is a schematic illustration of a fluid pumping and fluid supplying arrangement for (a) pumping out sea water or brackish water from the internal volume in between the surface of the vessel 205 and the barrier 215; and (b) supply protective fluid into the internal volume in between the surface of the vessel of the object.

FIG. 8A is a sectional view of the marine vessel 205 with the corrosion protection system 200 shown in a fully raised configuration whereby the sea water has been pumped out of the internal volume.

FIG. 8B is a sectional view of the marine vessel 205 with the corrosion protection system 200 shown in a fully raised configuration whereby the protective fluid has been pumped into the internal volume.

FIG. 9 is a side view of the vessel 205 with the corrosion and fouling prevention system 200 installed thereon shown in a coupled configuration relative to a marine attachment assembly 235.

FIG. 10 is a top view of the corrosion and fouling prevention system 200 (marine vessel 205 removed for clarity) shown in a coupled configuration relative to a marine attachment assembly 235.

FIG. 11 is a side view of the corrosion and fouling prevention system 200 (marine vessel 205 removed for clarity) in a lowered configuration shown as coupled to a marine attachment assembly 235.

FIG. 12 is a side view of the corrosion and fouling prevention system 200 (marine vessel 205 removed for clarity) in a raised configuration shown as coupled to a marine attachment assembly 235.

FIG. 13 is a schematic illustration of the master controller 230 shown in communication with the first and second controllers 273 and 287.

FIG. 14 illustrates a side view of a system for preventing fouling and/or corrosion on a buoy in the sea 410, according to an embodiment of the present invention;

FIG. 15 illustrates a side view of a system for preventing fouling and/or corrosion on subsea machinery in the sea, according to an embodiment of the present invention;

FIG. 16 illustrates a schematic of a system for preventing fouling and/or corrosion on an object which is partially submerged in an aquatic environment, according to an embodiment of the present invention;

FIG. 17 illustrates a schematic of a system for preventing fouling and/or corrosion on an object which is fully submerged in an aquatic environment, according to an embodiment of the present invention; and

FIG. 18 illustrates a schematic of a system for preventing fouling and/or corrosion on an object which is partially submerged extending in an aquatic environment extending into the earth base, according to an embodiment of the present invention.

DETAILED DESCRIPTION

FIGS. 1 to 13 illustrate a corrosion and fouling prevention system 200 for preventing the fouling or corrosion of a vessel 205. In particular, the system 200 protects the hull of the vessel 205 and is provided to protect the vessel 205 from growth of barnacles, algae, and marine organisms thereon, and corrosion, both of which may otherwise occur if the vessel 205 was submerged in an aquatic environment 210, without protection. The aquatic environment 210 is generally an exposed body of water, such as a sea, river or lake, which contains barnacles, algae, and/or marine organisms.

The system 200 includes a flexible and non-permeable sheet 215 which is positioned near the hull of the vessel 205 to form a barrier and define a protection zone 220 adjacent to the vessel 205. During use, the sheet 215 extends about a surface of the hull 205 a of the vessel 205 to avoid direct contact between the surface 205 a and the seawater and/or brackish water of the aquatic environment 210.

Floatation devices 225 include attachment structures to allow attachment of the floatation devices 225 to the vessel 205 at a plurality of locations extend around the surface of the hull 205 a. The floatation devices 225 allow the non-permeable sheet 215 to be positioned in a spaced apart configuration relative to the surface 205 a of the hull to define an internal volume in between the surface of the vessel 205 a and the sheet/barrier 215 to receive a fluid that has a composition that is different to the aquatic environment. In an in-use configuration, the internal volume in between the surface of the vessel 205 a and the sheet/barrier 215 is filled with a protective fluid (e.g. fresh water) which is different to the seawater or brackish water of the aquatic environment 210.

FIG. 1A depicts an enlarged sectional view of a section 200A from FIG. 1. The aquatic environment 210 may comprise an ocean or a water body that is likely to promote growth of barnacles, algae, and marine organisms on the hull surface 205 a of the vessel 205 and cause damage thereto, or at least increase drag in the boat, which may increase fuel consumption. Similarly, without protection, metallic items on or around the hull 205 may undergo corrosion. The applicant has found that attachment of the floatation devices 225 around the hull 205 a of the vessel to suspend the barrier sheet 215 in a generally downward direction and filling the internal volume between the surface of the vessel 205 a and the sheet/barrier 215 with the protective fluid (having a composition that prevents or inhibits corrosion and fouling of the hull surface 205 a) results in the formation of the protection zone 220 that prevents fouling and corrosion of the boat 205.

The system 200 is preferably reusable, in that it can be opened or removed when the boat 205 is underway, and closed or reinstalled when the boat 205 is moored or anchored as will be explained in the foregoing sections.

The floatation device(s) 225 comprise a substantially hollow structure. In the presently described embodiment, the floatation devices(s) 225 take the form of hollow pipes (such as PVC pipes) comprising walls that enclose a hollow cavity for receiving a fluid into the hollow cavity. Referring to FIGS. 3 and 4, the floatation devices 225 are provided with respective fluid inlets 227 for allowing fluid to be filled into the cavities of the floatation devices 225. Each of the inlets 227 may be fluidly coupled with a pumping arrangement comprising a pumping device 270 controlled by a flow controller 273. The controller 273 may be actuated by a user in an initial step to pump a fluid such as fresh water using the pumping device 270 into the floatation devices 225. The fluid may be pumped from a reservoir 275. Supplying fluid into the cavity of the floatation device(s) 225 results in lowering or submerging the floatation devices 225 into the seawater and/or brackish water in a lowered position to allow the vessel 205 to be positioned above the corrosion and fouling prevention system 200. As evident from FIG. 3, lowering the floatation device 225 temporarily (by supplying fluid into the hollow floatation devices 225, as explained above) allows the vessel 205 to be moored into an initial position for installation whereby the vessel 205 is directly above the floatation devices. It is also important to note that during this initial installation step, sea water or brackish water from the aquatic environment 210 may enter the internal volume defined by the barrier sheet 215. The removal of this sea water or brackish water from the internal volume of the barrier sheet 215 will be discussed in the following sections.

Once the vessel 205 has been positioned substantially above the floatation devices (initial position-FIG. 3), water from the floatation devices 225 may be raised relative to the vessel 205 by removing fluid from the floatation devices 225. Once again the fluid inlets 227 may now be utilised for directing the fluid out of the floatation devices 225. Gradual removal of the fluid from the floatation devices 225 may be carried out by actuating the controller 273 to pump fluid out of the floatation devices 225 using the pumping device 270 to feed the pumped fluid back into the reservoir 275. FIG. 5 depicts the floatation devices 225 in a gradually raised configuration.

Referring to FIG. 6, once the fluid from the floatation devices 225 has been substantially pumped out or removed, the floatation devices 225 rise and become positioned at the surface of the sea water or brackish water in close proximity to the hull of the vessel 205. One or more vents 225 (See FIGS. 11 and 12) may be positioned to vent the cavities of the floatation devices 225 and release accumulation of air if the floatation devices 225 contain pressurised fluid in the one or more cavities.

The floatation device(s) 225 may be fastened or attached to the hull of the vessel at a plurality of attachment locations. The manner in which the floatation device(s) are fastened to the vessel 205 is not limiting and one or more conventional methods may be used for attachment of the floatation devices 225 to the vessel 205. In some embodiments, the attachment of the floatation device(s) to the vessel 205 may result in forming a sealing arrangement for sealing a portion of the sheet or barrier 215 relative to the vessel 205. Formation of such a seal allows the internal volume defined in between the surface of the vessel 205 and the barrier 215 to be fluidly sealed relative to the aquatic environment 210.

Upon attachment of the floatation devices 225 and formation of the sealing arrangement, the next step involves removal of any sea water or brackish water from the internal volume defined in between the surface of the vessel 205 and the barrier 215. A fluid inlet/outlet 217 is provided for removal of fluid from the substantially sealed internal volume. It must be understood that the location or structural configuration of the inlet/outlet 217 is not limiting. A secondary controller 287 may be actuated to commence a pumping operation that results in the sea water or brackish water being pumped out of the internal volume. Another pumping device 280 may be used for pumping out the sea water and directing the sea water into a reservoir 283. Alternatively, the pumped sea water may also be released into the aquatic environment 210. FIG. 8A depicts the system 200 in an emptied configuration (without any protective fluid in the internal volume).

Once the sea water has been removed from the internal volume, the protective fluid may be pumped into the internal volume by actuating the controller 287. Actuating the controller 287 results in the protective fluid being pumped from a protective fluid reservoir 285 into the internal volume defined by the barrier sheet 215 by introducing the protective fluid into the internal volume through the inlet/outlet 217 to form the protective zone 220 as shown in FIG. 8B.

Referring to FIGS. 9 to 12, the system 200 also comprises a marina attachment assembly 235 that is adapted to be coupled with the floatation devices 225 and the barrier sheet 215 to facilitate installation or removal of the corrosion or fouling prevention system 200 on the marine vessel 205. The marina attachment assembly 235 includes an extension member 238 extending outwardly from the marina M for attachment to the attachment structures of the floatation devices 225 at an attachment location such as attachment location 239 (See FIGS. 11 and 12). The extension member 237 is substantially elongate and pivots about a pivot point 237 to allow the distal end of the extension member 238 to be lowered or raised when the extension member 238 is pivoted about the pivot point 237. The marina attachment assembly 235, particularly the extension member 238 assists with the lowering or raising of the floatation devices 225 (attached to the extension member at attachment location 239) during installation of the corrosion and fouling prevention system 200 onto the vessel 205. Similarly, the marina attachment assembly 235, particularly the extension member 238 also assists with the lowering or raising of the floatation devices 225 (attached to the extension member at attachment location 239) during removal of the corrosion and fouling prevention system 200 from the vessel 205. FIG. 11 shows the system 200 in a lowered position whilst being coupled to the marina attachment assembly 235. FIGS. 9 and 12 on the other hand shows the system 200 in a raised configuration whilst being coupled to the marina attachment assembly 235.

The marina attachment assembly 235 may also provide one or more supply lines via a services hub 240 for supplying electricity and for supplying the protective fluid (e.g., fresh water) and other fluids (such as fluids pumped into the floatation devices 225). Additional supply lines may also be provided via a secondary hub 245. By way of example, the secondary hub 245 may be used for pumping out sea water or brackish water out of the internal volume of the barrier 215 (as shown in FIG. 8A).

Additional fluid couplings or connection points 243 and associated controllers may also be provided for providing additional control over fluid flow into and out of the floatation devices 225.

As shown in FIG. 13, the first controller 273 (that controls the fluid filling or fluid removal from the floatation devices 225) and the second controller 287 (that controls pumping out of sea water out of the internal volume of the barrier and filling the internal volume with protective fluid) may be electronically coupled to a master controller 230 (See FIGS. 9, 10 and 13). Furthermore, the master controller in at least some embodiments, may be positioned relative to the marina attachment assembly 235 to allow personnel stationed at the marina to easily install or remove the system 200 onto or from the vessel 205.

While the system 200 as described in the previous sections relates to marine vessels 205, the skilled addressee will readily appreciate that embodiments of the invention may be particularly useful for use around bridge structures which are partially or fully submerged in bodies of water, such as buoys, pylons and subsurface equipment.

FIG. 14 illustrates a side view of a system 400 for preventing fouling and/or corrosion on a buoy 405 in the sea 410, according to an embodiment of the present invention. The buoy 405 is anchored to a sea bottom 410 a by an anchor 415.

A non-permeable sheet 420 is placed around an underside of the buoy 405 and sealed against the anchor 415 on an underside using attachment 430, and against a periphery of the buoy 405 and an upper side, defining a protection zone 425 against a submerged portion of the buoy 405. The seawater is pumped out from the protection zone 425, and replaced by freshwater in a similar manner as explained in the earlier sections in relation to system 200.

According to certain embodiments, the buoy 405 may be configured to generate freshwater, and thus continuously replenish the freshwater in the protection zone 425. This is particularly advantageous if the protection zone 425 is not entirely sealed or for example if the sheet used is permeable in one direction only, as it enables nutrients or saltwater to be flushed from the protection zone either continuously or periodically.

FIG. 15 illustrates a side view of a system 500 for preventing fouling and/or corrosion on subsea machinery 505 in the sea 510, according to another embodiment of the present invention. The subsea machinery 505 is associated with an offshore platform 515 and a vessel 520, which provide above-sea services and control of the machinery 505.

In particular, the machinery 505 is tethered either to the offshore platform 515 or the vessel 520 by a tether 525. A non-permeable sheet 530 is placed around the machinery 505 and sealed against the tether 525 on one side, and against a periphery of the machinery 505 and an the other side, defining a protection zone 535 around at least part of the machinery 505. The seawater is pumped out from the protection zone, and replaced by freshwater, as outlined above.

Remote Operated Vehicles (ROVs) can be used to install such barriers. The tether 525 may be used to pump the saltwater from the protection zone, and provide the freshwater to the protection zone. The fluid can be displaced via the use of e.g. pumps, pressurized gas cylinders, bottles and compressors. Relevant fluid can be placed, replaced, removed or reinstalled into the protection zone 535, as outlined above. If the fluid required in the protective zone is potable water. In this regard, a desalination plant may be located on the offshore platform 515 and/or the vessel 520, together with pumps and the like, to enable such remote displacement of the saltwater around the machinery 505.

FIG. 16 schematically illustrates a system 600, for preventing fouling and/or corrosion on an object 1 that is (otherwise) semi-submerged in an aquatic environment 5, according to an embodiment of the present invention.

Much like the systems described above, a barrier 4 is provided adjacent to an underside of the object 1, which defines a liquid protection zone 2 around an underside of the object. This protects the object 1 from fouling and/or corrosion that would otherwise occur if placed directly in the aquatic environment 5. Furthermore, one or more devices, switches, valves, pumps and/or electronics 3 exist in the liquid protection zone 2.

An upper side of the object 1 is exposed to atmosphere 7, and thus does not need protection from the aquatic environment 5.

The barrier 4 may be configured to at least partially float in the aquatic environment 5 when in use, with a lower portion spaced from the earth base 6 of the aquatic environment 5. The barrier 4 can also be attached to the object 1 directly (e.g. around a periphery thereof), or to one or more other objects.

The barrier 4 may also transition between a raised and a lowered state. In particular, a portion of the barrier 4 may move or be moved out of the aquatic environment 5 and into the atmosphere 7 (and thus into the raised state), which is particularly useful in case the object 1 is a vessel and is berthed, moored or anchored. The barrier 4 may then be move or be moved back into the aquatic environment 5 (surrounding the object 1) (and thus into the lowered state), which is particularly useful when the vessel is in motion or is about to move.

FIG. 17 schematically illustrates a system 700, for preventing fouling and/or corrosion on an object 1 that is (otherwise) submerged in an aquatic environment 5, according to an embodiment of the present invention.

A barrier 4 is provided surrounding the object 1, which defines a liquid protection zone 2 around the object 1. This protects the object 1 from fouling and/or corrosion that would otherwise occur if placed directly in the aquatic environment 5. In contrast to the system 600, the object 1 is entirely encompassed within the liquid protection zone 2, and is thus not exposed to atmosphere 7 but is still separated from the earth base 6 of the aquatic environment 5.

FIG. 18 shows a system similar to that illustrated in FIG. 16 but in which the object 1 extends from above the waterline down into the earth base 6 of the aquatic environment 5. In this embodiment, the barrier is defined about the object with an upper portion configured to at least partially float in the aquatic environment 5 when in use, and a lower part is either sealed about or extends about a lower end of the object, preferably at least partially within the earth base 6 of the aquatic environment 5. The barrier 4 can also be attached to the object 1 directly (e.g. around a periphery thereof), or to one or more other objects.

While the above embodiments describe use of fresh, clean water, the skilled addressee will readily appreciate that other fluids may be used. As an illustrated example, fluid may comprise a gas (e.g. Carbon Dioxide, Argon or Nitrogen) or a mixture thereof. Preferably, the gas is substantially non-corrosive to the object, and may comprise an inert (or substantially inert) gas or a mixture of gases forming a substantially inert mixture.

The use of a gas may enable electrical instruments to be deployed in the area that are unable to function in a liquid, such as an electronic measurement device, relays, switches, sensors and the like.

Similarly, the water may comprise seawater (or water from outside of the protection zone) that has been treated with an additive. As an illustrative example, the additive may comprise a biocide and/or a corrosion inhibitor.

Furthermore, while the above embodiment describe use of a non-permeable sheet, the skilled addressee will readily appreciate that any suitable barrier may be used, and such barrier may, for example, comprise a plurality of sheets, or any other suitable structure that provides the barrier. In some embodiments, the barrier may include a frame.

In some embodiments, the barrier (e.g. a non-permeable sheet) is UV permeable. As such, ultraviolet radiation may penetrate the barrier, which may assist in the prevention of fouling. The barrier is preferably resistant to UV radiation, and as such, does not degrade in the presence of UV radiation.

As outlined above, electrical components may be located within the protection zone, including, for example, when the protection zone is filled with a gas. In such case, the barrier may include isolation properties, such as electronic insulation properties, which may prevent interaction of the electrical components with outside components. Furthermore, such barrier may also be provided for the purpose of safety, to further prevent electrical shock or injury to persons or animals in proximity to the barrier.

In addition to the objects described above that are made for water, embodiments of the present invention may be used to protect emergency devices in the water. In such case, the barrier may be gas filled, to prevent submersion of the emergency device in the water.

Some embodiments of the invention may be specifically configured to prevent cross-contamination between fluid (e.g. fresh water) in the protection zone and fluid (e.g. salt water) outside of the protection zone. As an illustrative example, the water from the protection zone may be retrieved (e.g. by a pump) prior to removal of the protection zone. Similarly, the systems may include the ability to exchange ballast and/or bilge water to prevent cross-contamination between different marine zones.

Embodiments described above enable an environment to be quickly and inexpensively created around an object which is at least partially or fully submerged in an aquatic environment, to prevent or reduce fouling, marine growth and/or corrosion (including oxidisation, rust, galvanic corrosion, and change due to electrolysis). As such, the environment around the object may be quickly and efficiently changed from one where marine growth and/or corrosion is sustained, to one where marine growth is not sustained and corrosion is inhibited.

The embodiments may be used on structures that are already submerged, and as such, there is no need to retrieve the object from the water, as is the case for anti-fouling painting and/or cleaning.

In compliance with the statute, the invention has been described in language more or less specific to structural or methodical features. The term “comprises” and its variations, such as “comprising” and “comprised of” is used throughout in an inclusive sense and not to the exclusion of any additional features.

It is to be understood that the invention is not limited to specific features shown or described since the means herein described comprises preferred forms of putting the invention into effect.

The invention is, therefore, claimed in any of its forms or modifications within the proper scope of the appended claims appropriately interpreted by those skilled in the art. 

What is claimed:
 1. A corrosion or fouling prevention system for preventing the fouling or corrosion of a vessel or an aquatic object having a surface in contact with seawater and/or brackish water in an aquatic environment, the system comprising: a flexible and non-permeable barrier that extends about a surface of the vessel or aquatic object to avoid direct contact between the surface and the seawater and/or brackish water, an attachment structure for attachment of the barrier relative to the vessel or aquatic object to position the barrier in a spaced apart arrangement from the surface of the vessel to define an internal volume in between the surface of the vessel of the object and the barrier to receive a fluid that has a composition that is different to the aquatic environment wherein the attachment structure comprises one or more floatation devices adapted for being positioned relative to the vessel or object and wherein during use the barrier is suspended in a generally downward direction relative to the floatation device to position the barrier in said spaced apart arrangement and wherein the floatation devices further comprise walls enclosing a hollow cavity for receiving and removal of fluid therein such that supplying fluid into the cavity of the floatation device results in lowering or submerging the entire attachment structure into the seawater and/or brackish water in a lowered position to allow said vessel or aquatic object to be positioned above the attachment structure; and a fluid removal arrangement to gradually remove fluid from the one or more cavities of the floatation device to raise the attachment structure to the surface of the seawater or brackish water to facilitate attachment of the barrier relative to the vessel or aquatic object and wherein the flotation devices further comprise one or more vents positioned to vent the cavities and release accumulation of air when the floatation devices contain pressurised fluid in the one or more cavities.
 2. A corrosion or fouling prevention system in accordance with claim 1 wherein the floatation devices are adapted to be attached to the vessel or object.
 3. A corrosion or fouling prevention system in accordance with claim 1, further comprising a flow controller for controlling the flow of fluid into or out of the one or more cavities of the floatation devices thereby effecting movement of the attachment structure.
 4. A corrosion or fouling prevention system in accordance with claim 1, further comprising: a pumping arrangement adapted to pump out sea water or brackish water from the internal volume in between the surface of the vessel of the object; and a fluid supply arrangement to supply the fluid that has a composition that is different to the aquatic environment into the internal volume in between the surface of the vessel of the object.
 5. A corrosion or fouling prevention system in accordance with claim 4, further comprising one or more coupling assemblies positioned relative to the barrier and/or the attachment structure, said coupling assemblies being adapted to be coupled to the pumping arrangement and/or the fluid supply arrangement.
 6. A corrosion or fouling prevention system in accordance with claim 4, for preventing the fouling or corrosion of a vessel having a surface in contact with seawater and/or brackish water in an aquatic environment in accordance with any one of the preceding claims further comprising a marina attachment assembly adapted to be coupled with the attachment structure and/or the barrier to facilitate installation or removal of the corrosion or fouling prevention system relative to the vessel.
 7. A corrosion or fouling prevention system in accordance with claim 6, wherein the marina attachment assembly further comprises an extension member extending outwardly from the marina for attachment to the attachment structure at one or more attachment locations wherein the extension member is adapted for movement in an upward or downward to facilitate upward or downward movement of the attachment structure relative to the vessel thereby facilitating installation or removal of the corrosion or fouling prevention system relative to the vessel.
 8. A corrosion or fouling prevention system in accordance with claim 7, wherein the marina attachment assembly comprising one or more connectors adapted to be fluidly coupled to the fluid supply arrangement and the pumping arrangement.
 9. A corrosion or fouling prevention system in accordance with claim 1, for preventing the fouling or corrosion of a vessel having a surface in contact with seawater and/or brackish water in an aquatic environment in accordance with any one of the preceding claims further comprising a marina attachment assembly adapted to be coupled with the attachment structure and/or the barrier to facilitate installation or removal of the corrosion or fouling prevention system relative to the vessel.
 10. A corrosion or fouling prevention system in accordance with claim 9, wherein the marina attachment assembly further comprises an extension member extending outwardly from the marina for attachment to the attachment structure at one or more attachment locations wherein the extension member is adapted for movement in an upward or downward to facilitate upward or downward movement of the attachment structure relative to the vessel thereby facilitating installation or removal of the corrosion or fouling prevention system relative to the vessel.
 11. A corrosion or fouling prevention system in accordance with claim 1, wherein the fluid received in the internal volume in between the surface of the vessel of the object and the barrier is fresh water.
 12. A corrosion or fouling prevention system in accordance with claim 1, further comprising a sealing arrangement for sealing a portion of the barrier relative to the vessel or the marine object to prevent the sea water or brackish water from being received into the internal volume in between the surface of the vessel of the object and the barrier.
 13. A method for corrosion or fouling prevention in a vessel or an aquatic object having a surface in contact with seawater and/or brackish water in an aquatic environment, the method comprising: positioning a flexible and non-permeable barrier that extends about a surface of the vessel or aquatic object to avoid direct contact between the surface and the seawater and/or brackish water; attaching an attachment structure relative to the vessel or aquatic object to position the barrier in a spaced apart arrangement from the surface of the vessel to define an internal volume in between the surface of the vessel of the object and the barrier; and supplying a fluid into the internal volume wherein the fluid has a composition that is different to the aquatic environment; wherein the attachment structure comprises one or more floatation devices adapted for attachment to the vessel or object and wherein the attachment step comprises suspending the barrier in a generally downward direction relative to the floatation device to position the barrier in said spaced apart arrangement; supplying fluid into a hollow cavity defined by walls of the floatation devices to lower or submerge the entire attachment structure into the seawater and/or brackish water into a lowered position to allow said vessel or aquatic object to be positioned above the entire attachment structure; and remove or pump fluid out of the hollow cavity of the floatation devices to gradually raise the floatation devices of the attachment structure to the surface of the seawater or brackish water for facilitating positioning of the barrier relative to the vessel or aquatic object.
 14. A method for corrosion or fouling prevention in accordance with claim 13, comprising an intermediate step of: pumping or removing any sea water or brackish water from the internal volume before the step of supplying the fluid into the internal volume in between the surface of the vessel of the object and the barrier.
 15. A method for corrosion or fouling prevention in accordance with claim 13, further comprising the step of coupling the attachment structure and/or the barrier to a marina attachment assembly to facilitate installation or removal of the corrosion or fouling prevention system relative to the vessel.
 16. A method in accordance with claim 15, wherein the marina attachment assembly further comprises an extension member extending outwardly from the marina, the method comprising the additional steps of: attaching the marina attachment assembly to the attachment structure at one or more attachment locations; lowering the extension member in a downward direction to facilitate downward movement of the attachment structure for positioning the attachment structure in said lowered position before positioning the vessel or aquatic object above the attachment structure; raising the extension member in an upward direction to facilitate upward movement of the attachment structure in the sea water or brackish water and positioning the attachment structure adjacent the vessel or the object at or along the surface of the sea water or brackish water. 